Drilling and countersinking tool



L. A. SMITH DRILLING AND COUNTERSINKING TOOL Dec. 11, 1945.-

Filed Dec. 25, 1942 m r u 0 r 3 W 4 m 4 r Patented Dec. 11, 1945 \-4'1-ZL.'. l\ ii unis-I) if DRILLING AND COUNTERSINKING TOOL Los Angeles, Calif assignor to Robert This invention relates to toolsaandrrelates more particularly. to acomb'ina'tion drilling. and countersinking tooL- A general o'bject onthishinvention is to'pr'ovide a simple, practical and particularly effective too'li operable to drill an -opening or bore and fornra counterbore or countersink inth'e same operation a 7 1 i it In many structures and devicesit is necessary to "provide openings for the reception-of screws, bolts, etc. and to formdepressionsor countersinks at the mouths of such openings to-reeeive the heads of thescrews or bolts. In providing such-openings it-has been the general practice to drill the opening in one operation and'then the countersink or depression in a separate operation and with a separate tool This has necessitated the provision and maintenance of separate drilling and countersinking tools and the carrying "on of two distinct series of operations. I I

m ne; object a: this i'memi(snis to provide a single tool that "serves to c'lepe'ridably support a drillof the selected type a'na size for drilling an opening or bore and that also carries or is provided with means for :countersinking at the mouth of the bore j'ronthe completion of the bore and in theselfes'ame (inflation. In :e mploy ingthe tool of the present invention an opening or bore and a lee formed ln'ra p id succession in one operation.

.v th rb sia. ,t, lr fibi s vbi'iivide a ,tool of the character mentioned. in which the cour'itersink means is r readily removable so that it may be sharpened orrepla'cedby a countersink means, designed tio form, a jcounterbore, or: countersink of different diameter or configuration.

Another objectof this invention is to provide a tool of the characten referredto. in whichnthe countersink Ineansisin the renter, a simple unit that is readily installed, replaced and 'resharpened. Another and importantobjectof this invention is to provideaitool of the characterreferred to whose body is in the nature of an adapter, socket or holder adapted to be inserted inthe spindle of a drilling machine or thewlike, and capable of reinovably supporting a .drill fornperation thereby} which body also serves to carry a simple efiective means for c'oun tersinking. Considered one light the device of the present invention is the nature of a socket or drill holder embojdyintg a countersink,

Another object of this iii ei t bh is tbji i ia' a tool of the character mentioned in which the shoulder I5. w extends forwardly from the shoulder. l5. :A- cen- H. Clark, Los Angele s Calif eniiir 2s, 1942, Serial No. 469,860 i'cl'aiihs. (01 77-6 countersink means presents cutting edges-which extend inwardlysto-the drill, leavingnqgappr Dace. in-'W1'1iGh cuttin s can lec ia dr enr ing the formation of a burr around the drilled bore. r 2 1 .Aiurthen object of this invention. is to prgoyide a drilling and counter-sink ng tool ofthe char acterreferred to-that may be set oradjusted to form a count'erbore or countersink of any selected depth. I i- "1- Q lent l.

The various objects andfeatures got my invert tionwill be fully understood from the iollowi-ng detailed. description of v typical; preferred 1 iOl-ms andrapplications ofmny invention, throu hou which-descriptionJreference;is made to the accompanying drawings in which:.- 1. a Fig. 1 is a longitudinal detailed sectional view of one form of. tool oftheinventionshowingithe upper portion of the body in side elevation. 2. is: an enlarged end =vview. of. the. v.tool illustrated inf-is.- 1-andMFigw3 is a yiew; similar ,toiFig. 1 illustrating. another form oft-the invention. v The embodimentoi the invention;illustrated inhFigs. 1 and 2 of the drawing .maybe saidto comprise, generally, a body; l0. formed: to carry a drill l l andcountersink means 12 on the body.

The body It is an elongate member adapted to lee-carried and operated by aY-machine'tool-or drilling- 7 machine useful Yin-1 performing. drilling and countersinking r operations; The body :IO may be shaped and proportioned to be.re.oeived or rotated by-mechanisms and: tools of-different kinds In the drawing the body I has aimore or-less conventionalv shape, being round intransverse cross section and being. longitudinally 7-stapered toward its inner. end. Aflat tang is provided on the innerend of the body H] to. facilitate the-transmission of rotation to thebody. The forward or outer portion of the body "I is shaped to carry the drill H and the countersink :means I2; A forward end portion l4 of thebody 1.0. is cylindrical and terminates .at an annulan radial A stem l6 ofreduced. diameter trallongitudinal opening IJ extends throughlthe stem 16 and enters the body proper. i The ,openmg IT is provided to-re'ceive the shank l8 of the drill H and-as illustrated may be asimple bore of uniform diameter. It is to be observed that the body 10 may be a simple, inexpensively produced one-piece member. 1 t 4 :Ifhe invention contemplates the employment-of drills o'f difierenttypes', diameters, and-lengths 'and the drill ll disclosed'in-thedrawing r-issto be considered as merely illustrative or typical.

The drill II shown is short, and of the kind useful in center boring and in drilling through thin stock or sheet stock, it being obvious that the drill may be of any length. The shank I8 of the drill I I is received or engaged in the body opening I1 and it is preferred to provide means for positively transmitting rotation from the body I!) to the drill. The means for transmitting rotation from thebody to the drill may take various forms. In the'simple case illustrated the inner portion of the shank I8 has an elongate flat surface I9 and a pin is engaged in a transverse opening in the body III to cooperate with the surface I9. The opening which carries the pin 20 partially intersects the opening I! so that the pin 20 protrudes into the opening I! to engage with the flat shank surface 20.

I prefer to rovide the drill I I with an annular inwardly facing shoulder 2I at the outer terminus of its shank. The shoulder 2I allows the countersinking means I2 to extend inwardly to or beyond the effective diameter of the drill II as will be more fully described. The shoulder 2I need not be extensive and it is exaggerated in width in the drawing for the purpose of'illustration. The shoulder 2| is spaced some distance from the forward end of the body stem I 6.

The countersink means I2 is a feature of the invention. The means I2 is operable to form a counterbore or countersink at the mouth .of the opening bored by the drill I I immediately following the drilling of said bore, and in the same operation of the tool, it being merely necessary to continue the feed or advancement of the tool' to 'form the counterbore. In the embodiment of the invention being described the countersink means I2 is a simple unit, comprising a member 22 removably screw-threaded on the stem I6 and provided with axially projecting cutting parts 23.

The inner end of the threaded member 22 is plain and'flatand is adapted to bear on the body shoulder I5. It is to be observed that the engagement of the member 22 with the shoulder I5 definitely positions or locates the cutting parts 23. The periphery of the member 22 may be substantially flush with the exterior of the body portion I4 and may be knurled or provided with flat faces to facilitate the threading of the member. The tubular member 22 is preferably of sufficient length to extend to or beyond the end of the stem I6.

The cutting parts 23 of the countersink means I2 extend from the outer end of the member 22 and converge inwardly to or toward the'drill II. The nature, shape, and number of the cutting parts 23 may be varied, depending upon the nature of the intended operations and .the shape of the counterbore or countersink to be formed. The cutting 'parts'23 maybe formed to produce a counterbore or countersink depression of any selected diameter and depth with walls at the selected pitch or angle. -In the case illustrated the cutting' arts 23 are formed to produce a frusto-conical or tapered countersink depression around the mouth of the bore formed by the drill II and the cutting parts 23 are shaped so that the walls of the countersink will have a substantial pitch. Ihave shown three circumferentially spaced cutting parts 23 separated by substantial chip-clearing spaces or notches 2d. The cutting parts 23 may be dressed or ground, as required. As illustrated the cutting parts 23 have cutting edges which are substantially radial with respect to the drill II and which converge downwardly and inwardly toward the drill. The cutting edges 25 may extend to the inner lower extremities or cutting parts 23. It is preferred to have the cutting edges 25 extend to or behind the shoulder 2I to act on the work from immediately at the periphery of the drill II and outwardly therefrom, so that there is no space or gap around the drill in which cuttings may collect or in which a bead or burr may be formed. The above described shoulder 2| permits the cutting edges 25 to extend inwardly to the shank I8 of the drill or at least to a point behind the shoulder, leaving absolutely no gap between the effective diameter of the drill and the active inner diameter of the countersink cutting parts 23.

It should be observed that the countersink means I 2 is embodied in a simple one-piece unit. The countersink means I2 may be easily removed for replacement by a countersink unit having cutting parts 23 of different formation, of diiferent diameter, etc. and the countersink unit may be easily removed for redressing and then readily replaced. The countersink means I2 may be embodied in a member 22 which is integra1 as initiallyformed, in which case it is constructed of steel or material capable of being hardened or tempered to retain effective cutting edges 25. In other cases it maybe preferred to braze or otherwise join cutting parts of special cutting material, such as high speed steel or the like, to the tubular member 22 or to legs on the member 22, in which case the member 22 need not be constructed entirely of cutting material.

The tool of the invention may include an adjustable stop 26 for limiting the depth of the counterbore or countersink and operable to render the countersink means I2 ineffectual when it is desired to perform drilling operations without countersinking. The stop 26 may be a simple sleeve threaded on the. cylindrical body portion I4 to be readily adjustable along the body. The stop 25 extends outwardly around the member 22 and may be proportioned so that it may be adjusted to a position to prevent the cutting parts 23 from engaging the work. In Fig. 1 the stop 26 is shown in an intermediate position where it limits the depth of the counterbore or countersink that may be formed by the cutting parts 23. the cutting parts 23 are effective throughout their extents. The outer end of the stop26is flat to evenly ride on the work. One or more openings 27 may be provided in the wallof the stop 26 adjacent its outer end to discharge the cuttings or chips.- A lock nut or jamb nut 28 may be threaded on the body portion I4 to set or retain the stop 26 in the selected position.

v In the use or operation of the tool illustrated iniFigs. l and 2 of the drawing a countersink member l2 having cutting parts 23 of the selected type and configuration is threadedon the body stem I6 and a drill II' of the selected kind and diameter is secured to the body II! by entering its shank I8 in the opening I! so that its flat surface I9 cooperates with the pin 20. It is to be understood that a set of members 22 may be provided with the tool so that the tool is capable of forming a wide range or selection of counterbores and countersinks ofdiiferent sizes and configurations and a set of drills of difierent sizes and kinds may likewise be provided. With the member 22 and the drill II conditioned for use the stop 26 is adjusted to the selected position and is locked in place by thejamb nut 28. With the body I0 engaged in thespindle of the drill, drilling machine, or the like; the actual drilling operations are carried on in the usual manner.

The stop 26 may be fully retracted so that Wl 1en the drill l l is advanced or fed intothe work theadvancement-may be continued-so that the cutting parts 23 engage "the work to f-orm the "counterbore or 1 countersink at the mouth of "the opening. 'Thus the countersinking operation is merely a continuation of the drilling operation and the drilled bore and the: countersink are'both formed-in one-continuous operation. The drill I l forms 'apilotor centering means for'the cutting parts23 of the countersinking-means-and'the "cuttingpar-ts "23 engaged with the drill or the drill shank stabilize and brace the drill. Both the drill I l andthecountersinking means I! may be easily removed from thebody ill for sharpening orfor replacement by drills and countersinking means i of different diametersgetc.

The form-of the invention illustrated inFig.

3 maybe said to comprise, generally, a body l for carrying a drill l and a countersinking means the outer end of the portion Ill and a reduced stem [6 continues forwardly from the shoulder IS. A central longitudinal opening Il extends through the stem Mi and enters the body m The drill H may be the same as described above, or may be any other selected or required kind of drill. I have shown the plain shank I8 of the drill ll arranged in the opening I! of the body l0 to have its flat surface l9 cooperate with the driving pin The drill II is positioned so that its shoulder 2| is spaced forwardly from the end of the stem I B The countersink means l2 includes a member 22*- in the form of a collar or sleeve engaged on the stem l6 of the body. The member 22 is adapted to be slid onto the stem ll'i so that its inner end bears against the shoulder le Means is provided for positively transmitting rotation from the body ll) to the member 22 In the simple form of the invention illustrated this means comprises a pin fixed to the body H! to project axially from the shoulder I5 A socket 3| is provided in the inner end of the member 22 to receive the pin 30 for the transmission of the turning forces from the body to the member.

Cutting parts ?3 project from the outer end of the member 22 and are shaped or dressed to form a counterbore or countersink depression of the required diameter and configuration. I have shown the cutting par-ts 23 similar to the cutting parts 23 described above, it being understood that they may be of other formations if required. The cutting parts 23 eXtend axially and converge forwardly and inwardly so that their ends may engage behind the shoulder 2| of the drill II, This leaves no gap between the drill and the cutting parts 23 The countersinking means l2 further includes a collar or sleeve 33 for retaining 'the member 22 on the body Ill The collar 33 is screw threaded on the cylindrical body portion I l and extends forwardly to surround the member 22 An internalinwardly facingshoulder 34 is provided on the collar 33 and opposes an outwardly facing external annular shoulder 35 on the member 22 If desired the shoulder 34 may directly cooperate with the shoulder 35 to clamp the member 22 against the shoulder l'a'e and thus hold the member in its operative position. In

the 'eonstruction illustrated shims 36 are en- --'gaged'-b'e'tween the shouldersfl and 35. The shims- 3B" st'op orl'ocate'the collar -33'so that its lower-end'may"cooperate W'ith'the work'to serve "as a stop for determining the depth'of the counterbore-or counte'rsin'k. By changing the'thickornum'b'er of shims 36 the collar 33 may be adjusted so that thetool will form counterbores "orcountersi'nk depressions of diiferent depths.

The operation of the tool illustrated in'Fig. 3 of the drawing is substantiallythe same "asthe operationdescribedabove. In this form of the inyention a drill II 'of the 'sele"cted diameter, l'ehgth'and type is engaged in the'opening "I? and the member 22 carrying cutting parts "23 for forming 'a countersink'of the required'size and shape is engaged on the stem Is '50 that its socket 3! receives the pin30. The collar '33 is'then threaded on-the body to retain the'member -2 2 in position. The collar 33 may be ad justed by means'of th "shims'36 to serve as a stop, if this is desired. The drilling and countersinking operation is performed in the manner above described.

Having described only typical preferred forms and applications of my invention, I do not wish to be limited or restricted to the specific details herein set forth, but wish to reserve to myself any variations or modifications that may appear to those skilled in the art or fall within the scope of the following claims.

Having described my invention, I claim:

1. A drilling and countersinking tool including a, body having an opening entering its forward end to receive and directly support a drill so that the drill may extend from said end of the body, a tubular member removably supported on the forward end portion of the body, means positively stopping the member against longitudi- 40 nal movement on the body, and countersink cutting parts on said member projecting from said end of the body around the drill, the dril1 having a shoulder spaced from and opposing said end of the body, said cutting parts extending inwardly toward the drill to engage behind the shoulder.

2. A drilling and countersinking tool including an elongate body having a reduced stem projecting from its forward end and an opening extending longitudinally through the stem and adapted to receive a drill so that the drill projects from the end of the stem, a member surrounding the stem to be removably supported thereon, countersink cutting parts projecting axially from said member and adapted to engage about the drill, and a collar threaded directly on the exterior of the body and engaging the member to clamp it against said end of the body.

3. A drilling and countersinking tool including an elongate body having a reduced stem at its forward end and an opening extending longitudinally through the stem and adapted to receive a drill so that the drill projects from the outer end of the stem, an annular member removably engaged over and supported on the stem, countersink cutting parts projecting axially from said member and adapted to engage about the drill, a collar threaded on the body for clamping the member against said end of the body, the collar being adapted to engage the work to limit the depth of the cut made by said parts, and one or more shims between the member and collar for locating the collar.

4. A drilling and countersinking tool including a shank, an externally threaded head on the forward end of the shank, a stem projecting from the forward end of the head and having an opening to support a drill so it projects forward from the stem, an annular member supported on the stem in engagement with the forward end of the body, countersink cutters projecting forward from said member, and a stop: sleeve threaded on the head to extend over said member and beyond the end of the stem.

5. A drilling'and countersinking tool including a body, an annular member supported on the forward end of the body, countersink cutters projecting forward from said member, a drill carried by the body to project beyond the cutters, and a single sleeve threaded to the body engaging said member to hold it on the body and projecting forward from the body to act as a stop.

6. A drilling and countersinking tool including a shank, an externally threaded head on the forward end of the shank, a stem projecting from the forward end of the head and having an opening to support a drill so it projects forward from the stem, an annular member supportedon the stem,- countersink cutters projecting forward from said member, and a stop sleeve threaded on the head to extend over said member and beyond the end of the stem and engaging said member to hold it on the stem.

7. A drilling and countersinking tool including a shank, an externally threaded head on the forward end of the shank, a stem projecting from the forward'end of the head and having an opening to support a drill so itprojects forward from the stem, an annular member on the stem to bear against the forward end of the body and having an outwardly facing shoulder, countersink cutters' projecting forward from said memher, and a stop sleeve threaded on the head to extend over said member and beyond the end of the stem and having an inwardly facing shoulder b'earing against the outwardly facing shoulder of the annular member.

LAWSON A. SMITH.- 

